Month: September 2014

ME-EM Graduate Seminar: In situ Nanoscale Testing to Validate and Elucidate Mechanism for Predictive Modeling

sep11The ME-EM Graduate Seminar speaker on Thursday, September 11 at 4:00 in 103 EERC will be Dr. Kahlid Hattar from Sandia National Laboratory. The title of his presentation will be ‘In situ Nanoscale Testing to Validate and Elucidate Mechanism for Predictive Modeling’.

Topic: In situ Nanoscale Testing to Validate and Elucidate Mechanism for Predictive Modeling

Predicting performance margins of complex systems requires the development of multiscale physics based models that incorporate potential processing, microstructure, and property variations. To create the necessary set of models, a fundamental understanding of the physics governing the associated materials interplay and response in the expected environments of operation is essential. In situ transmission electron microscopy (TEM) experiments validated by welldesigned bulk tests provide an excellent tool to elucidate the underlying mechanisms that govern the properties of materials exposed to various environmental conditions of interest.
This presentation will demonstrate the breadth of in situ TEM research capabilities that are now available to the materials science community. These capabilities will be highlighted through a set of three experimental examples. In the first set, both the detrimental and beneficial effects of ion irradiation in face-centered cubic metal will be demonstrated.
The detrimental effect will be shown through a detailed comparison of displacement damage on the microstructure and mechanical properties of high purity Cu whereas the beneficial effect will be presented for Au electrical contacts. Recent advancements in in situ TEM stages permit studies in gas and liquid environments. To demonstrate the potential of these stages, recent work done at Sandia to understand the uptake and release of hydrogen in nanoporous Pd nanoparticles and the nanoscale mechanisms of corrosion in high purity Fe will be shown. Finally, the presentation will highlight the ability of in situ ion irradiation studies to investigate the structural evolution of advanced nanoscale detectors under controlled radiation environments.
This research was partially funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.

Khalid Hattar is a Senior Member of the Technical Staff of Sandia National Laboratories. He
received a B.S. in Chemical Engineering from University of California, Santa Barbara in 2003, and a
Ph.D. in Materials Science and Engineering from University of Illinois, Urbana-Champaign in 2009.
He joined the Radiation-Solids Interaction group at Sandia in December 2008. He specializes in
determining the property-microstructure relationship
for a variety of structural, electrical, and optical
materials through in situ TEM in various extreme
environments.

Greg Odegard Named MEEM Associate Chair, Director of Undergrad Studies

Odegard2Tech Today by Marcia Goodrich, senior content specialist

Greg Odegard has been named the new associate chair and director of undergraduate studies for the Department of Mechanical Engineering-Engineering Mechanics, William Predebon has announced.

“I am extremely pleased that Greg has agreed to serve in this position,” said Predebon, chair of the department. “He has been recognized by his students as an excellent teacher and graduate student mentor, as well as an internationally recognized research scholar in his field, all of which are very important as the associate chair and director of undergraduate studies.

ME-EM Graduate Seminar: From carbon nanotubes to crowd noise: An overview of interesting topics in acoustics

barnardThe ME-EM Graduate Seminar speaker on Thursday, September 4 at 4:00 in 103 EERC will be Dr. Andrew Barnard, Mechanical Engineering – Engineering Mechanics, Michigan Technological University.

The title of his presentation will be ‘From carbon nanotubes to crowd noise: An overview of interesting topics in acoustics’.

Carbon nanotube (CNT) thin-films are ultra-lightweight, semi-transparent, flexible, and stretchable, films that can create sound through thermoacoustics. CNT thermophones have the potential to replace moving coil transducers and expand the applications of modern loudspeakers through “singing” fabrics. The fundamentals of CNT thermophone operation and key research challenges will be presented.
Underwater acoustics encompasses many disciplines and applications from Navy ships to oil exploration to climate change. Michigan Tech is located in an ideal location, on the shores of Lake Superior, to perform experimental underwater acoustics research through the Great Lakes Research Center (GLRC). Several topics in underwater acoustics will be discussed.
Transducer arrays and wavenumber domain signal processing provide a powerful way to visualize acoustic fields. An overview of techniques including supersonic intensity in reverberant environments (SIRE), and wavenumber processing of panel-to-panel transmission loss will be discussed. Current panel transmission loss (TL) measurement standards are woefully inadequate. Several test facilities can test the same specimen and the results can vary by more than 6 dB. Although panel TL theory is well developed, understanding of the fundamental measurement error is not. Insight into the field diffusivity in the source room will be discussed as well as paths towards an improved measurement standard. Smart controls systems are leading the way towards the realization of cyber-physical systems. An overview of the utility of FPGA-based control systems will be presented. These systems are particularly well suited for safety-critical control applications. Crowd noise is a much discussed topic in the mainstream media. Unfortunately most of the ad-hoc measurements that have been promoted are lacking in scientific rigor. Sound level measurements from Penn State football games will be presented to demonstrate how we can better measure this interesting phenomenon.

Dr. Andrew Barnard is a new assistant professor in the ME-EM department at Michigan Tech. He holds a B.S. and M.S. in mechanical engineering from MTU and a Ph.D. in Acoustics from Penn State. Dr. Barnard is Board Certified by the Institute for Noise Control Engineering and is a Certified LabVIEW Developer.
He spent the last 8 years working as a research faculty member at the Applied Research Laboratory at Penn State, specializing in structural acoustics. Dr. Barnard has general interests in mechanical vibration, noise control, and acoustics.
His specialties include dynamic test and measurement, underwater acoustic intensity, experimental modal analysis, room acoustics, acoustic material characterization, outdoor sound propagation, theoretical acoustics, signal processing, and real-time control systems. Other interests include loudspeaker design and fabrication, architectural acoustics, and engineering education.